Test systems with a probe apparatus and index mechanism

ABSTRACT

A probe apparatus has probe wires with a contact pattern on one side. The contact pattern is for contacting a respective contact pattern on another test equipment or component, such as a circuit board. The probe wires have tips that probe a device desired for testing. Signals are transmitted through the probe wires from the probe card, for example, through a circuit board to other diagnostic equipment. The contact of the probe card with the circuit board allows signals to be transferred through the probe wires to the other diagnostic equipment. On another side of the probe card is a connector structure. The connector structure includes a retainer that can allow the probe card to be replaced from a test system, such as allowing it to be connected and disconnected from a holder.

This application claims the benefit of U.S. Provisional Application No.61/504,907 filed on Jul. 6, 2011 and titled TEST APPARATUS HAVING PROBECARD AND CONNECTOR MECHANISM, the entirety of which is incorporated byreference herewith. This application also claims the benefit of U.S.Provisional Application No. 61/592,760 filed on Jan. 31, 2012 and titledTEST APPARATUS WITH A PROBE APPARATUS AND INDEX MECHANISM, the entiretyof which is incorporated by reference herewith.

FIELD

This disclosure relates generally to test equipment and systems,particularly for testing a semiconductor device. More particularly, thedisclosure herein relates to systems and apparatuses that have a probecard that can be used with other test equipment for electrically probinga semiconductor device, such as a semiconductor wafer or amicro-electrical-mechanical systems (MEMS) device.

BACKGROUND

Wafer probing and testing, for example in the semiconductor industry,could be made more efficient and accurate. As the semiconductor industrygrows and devices become ever smaller, the equipment required to testthe wafers has become more complex and expensive. Complex and expensiveequipment must be utilized efficiently in order to maximize the returnon investment, and complexities of testing requirements mean that theequipment must have diagnostic tests performed efficiently as well.Probe cards used to probe the wafers deteriorate electrically andmechanically with use as probes wear out and as the probes pick upparticulate. Currently to replace the probe cards as they wear out, theprober and tester must be stopped while the probe card is replaced.Replacing the probe card takes several minutes—time that could be usedtesting wafers. The act of replacing the wafer can also change themechanical fit of the wafer/probe card/prober/test head system resultingin different electrical results. The post card change verification canmore than double the down time.

SUMMARY

It would be useful, for example, to reduce the need to stop testequipment to replace a probe card and to improve utilization andelectrical performance in wafer testing. Test systems, apparatuses, andequipment are described that are useful, for example, in systems to testa semiconductor device. More particularly, a probe apparatus isdescribed that can be used to electrically probe a semiconductor device,such as a semiconductor wafer or MEMS device.

Generally, the probe apparatus is structured as a probe card that has acontact pattern of probe wires on one side. In some embodiments, theprobe wires may be gold plated. The contact pattern is for contacting arespective contact pattern on another test equipment or component, suchas a circuit board. The probe wires also include tips that probe adevice desired for testing, such as a device under test (DUT) forexample in semiconductor testing. Signals are transmitted through theprobe wires from the probe card, through the contact of the probe cardinsert or core and the circuit board, and through the circuit board toother diagnostic equipment. The contact of the probe card with thecircuit board allows signals to be transferred through the probe wiresto the other diagnostic equipment.

Also on the probe card is a connector structure, for example on anotherside of the apparatus. The connector structure allows the probe card tobe connected or disconnected from a holder.

In one embodiment, the connector structure includes a socket mount thatcan be connected, for example to a holder such as by connecting thesocket mount of the connector structure to a connector structure on theholder. In some examples, the connector structure on the holder is amating connector, such as ball mount, which can allow slight movement,such as tilting movements, of the probe card to facilitate good contact,for example to a circuit board.

In one embodiment, the holder allows for a probe card to be replacedwith another probe card, such as for example, another probe card with adifferent contact pattern or another probe card that may be areplacement for a worn out or used probe card. In some embodiments, theholder has multiple probe cards connected to it, and is configured toallow for interchanging among the probe cards connected to the holder,such as for changing a probe card between testing. In some embodiments,the holder is part of a system of components used to test devices, wherethe holder is able to manipulate and position the probe card as needed.

With further reference to the probe card, in one embodiment a probe cardhas a wire guide, a probe tile connected with the wire guide, and aplurality of probe wires supported by the wire guide and probe tile.Each probe wire is positioned through the wire guide and the probe tile.Each wire includes a probe tip extending through the probe tile. Theprobe tips are configured to probe a device, such as a semiconductorwafer. Each wire may also include a signal transmitting portion and aguard portion exposed from the wire guide. The signal transmittingportions and the guard portions form a contact pattern. This contactpattern is for contacting a signal contact and guard contact pattern onanother equipment, such as a circuit board.

In one embodiment, the probe tips and the contact pattern of the probecard are on one side of the probe card. On the other side of the probecard is a connector structure. The connector structure is configured toallow the probe card to be connected and disconnected to a holder. Inone embodiment, the connector structure is a retainer member that has aretention slot.

In one embodiment, a probe card such as described above is incorporatedas part of a test system, apparatus, or equipment, where the probe cardhas a contact pattern that matches a contact pattern on another testequipment or component, such as for example a circuit board ormotherboard. The probe card described herein also can be part of anoverall system for testing devices, such as semiconductor devices. Forexample, the connector structure of the probe card allows it to beconnected to a holder, where the holder is part of a system ofcomponents for testing devices and is able to manipulate and positionthe probe card as needed. For example: a traditional wafer probermachine.

In one embodiment, a method of probing devices under test comprisespositioning a holder into a probe position, positioning a probe needlearray onto a device under test using the holder, probing the deviceunder test using the probe needle array, and transmitting signalsthrough the probe needle array to a test equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings, which are not necessarily drawn to scale, illustrategenerally by way of example, but not by way of limitation, variousembodiments discussed in this application.

FIG. 1 is a bottom perspective view of one embodiment of a probeapparatus, such as a probe card.

FIG. 2 is a bottom view of the probe apparatus from FIG. 1.

FIG. 2A is another bottom view of the probe apparatus of FIG. 1.

FIG. 2B is a sectional view of the probe apparatus of FIG. 1.

FIG. 2C is a side view of the probe apparatus of FIG. 1.

FIG. 3 is a top view of one embodiment of a circuit board.

FIG. 3A is another top view of the circuit board of FIG. 3.

FIG. 3B is a side view of the circuit board of FIG. 3.

FIG. 3C is another top view of the circuit board of FIG. 3.

FIG. 4 is an exploded view of the probe apparatus of FIG. 1.

FIG. 5 is a close-up view of the probe apparatus of FIG. 1.

FIG. 6 is a sectional view of the probe apparatus of FIG. 1.

FIG. 6A is another sectional view of the probe apparatus of FIG. 6.

FIG. 7 is another sectional view of the probe apparatus of FIG. 1.

FIG. 8 is a perspective view of one embodiment of a holder.

FIG. 9 is a perspective view of the holder of FIG. 8 prior to connectionwith a probe card.

FIG. 10 is a perspective view of the holder of FIG. 8 shown connected toa probe card.

FIG. 11 is a bottom perspective view of another embodiment of a probeapparatus.

FIG. 12 is another perspective view of the probe apparatus of FIG. 11.

FIG. 13 is another perspective view of the probe apparatus of FIG. 11.

FIG. 14 is a partially exploded view of the probe apparatus of FIG. 11.

FIG. 15 is a perspective view of one embodiment of translationalindexing of multiple probe apparatuses.

FIG. 16 shows another perspective view of the translational indexingshown in FIG. 15.

FIG. 17 is a top perspective view of another embodiment of a probeapparatus.

FIG. 18 is a bottom perspective view of the probe apparatus of FIG. 17.

FIG. 19 is a sectional view of the probe apparatus of FIG. 17.

FIG. 20 is another sectional view of the probe apparatus of FIG. 17.

FIG. 21 is a perspective view of one embodiment of a testing system.

FIG. 22 is sectional view of the testing system of FIG. 21.

FIG. 23 is a partial sectional view of the testing system of FIG. 21.

FIG. 24 is another sectional view of the testing system of FIG. 21.

FIG. 25 is another sectional view of the testing system of FIG. 21.

FIG. 26 is another partial sectional view of the testing system of FIG.21.

FIG. 27 is top plan section view of the testing system of FIG. 21.

FIG. 28 is an isometric view of one embodiment of a loading tool.

FIG. 29 is a perspective view of one embodiment of packaging for atesting system.

FIG. 30 is a top perspective view of another embodiment of translationalindexing of multiple probe apparatuses.

FIG. 31 is a top view of the translational indexing of multiple probeapparatuses shown in FIG. 30.

FIG. 32 is a bottom perspective view of the translational indexing ofmultiple probe cards shown in FIG. 30.

FIG. 33 is perspective view of the probe shown in FIG. 30.

FIG. 34 is another perspective view of the probe shown in FIG. 30.

DETAILED DESCRIPTION

FIGS. 1-7 show one embodiment of test equipment that can be used in asystem to test devices, such as for example semiconductor devices,including but not limited to semiconductor wafers or other MEMS devices.Particularly, test systems, apparatuses, and equipment are described.Generally, a circuit board and a probe card can be used to electricallyprobe a semiconductor device, such as a semiconductor wafer. The probecard contacts the circuit board. The probe card has probe wires that canprobe the device to be tested and transmit signals from the probe cardto the circuit board. The circuit board transmits signals from the probecard for example to other testing equipment.

FIGS. 1, 2, and 2A-C show one embodiment of a probe card 10. The probecard 10 has a wire guide 16. A probe tile 14 is connected with the wireguide 16 (shown in FIG. 6). The wire guide 16 provides a groove pattern12 for probe wires to be configured into a contact pattern for example,for contacting a circuit board 40 (described further below). As shown inFIGS. 4-6A, a clamp 18 is used to secure probe wires within the groovepattern 12 of the wire guide 16. The clamp 18 has grooves 37 thatcorrespond to each of the grooves of the pattern 12 on the wire guide16. As shown, the grooves of the wire guide 16 may have a radiusedsurface, which can further facilitate alignment and eliminate mismatchof the contact between the probe card 10 and the circuit board 40.

A plurality of probe wires 30 are supported by the wire guide 16, clamp18, and probe tile 14. For ease of illustration, one probe wire 30 isshown (see FIGS. 6 and 6A). However, it will be appreciated that a probewire 30 may reside within each of the grooves of the groove pattern 12provided by the guide 16 and grooves 37 of the clamp 18.

With further reference to FIGS. 6 and 6A, each probe wire (see probewire 30) would be positioned through grooves of the wire guide 16 andclamp 18, and a channel 15 of the probe tile 14. As shown, the grooves37 of the clamp 18 in one embodiment are smaller relative to the groovepattern 12 of the wire guide, which can allow the clamp 18 to limitmovement of the probe wires 30 after assembly. The channel 15 allows theprobe wire 30 to be inserted into and through the probe tile 14 to anopening 17.

The probe wires 30 provide the probing function of the probe card 10.Each probe wire 30 would include a probe needle 32 with a probe tip 33that extends through the probe tile 14. For example, the probe needles32 and tips 33 may be disposed toward the center of the probe tile 14,where the tips are exposed from the probe tile 14 generally at thecenter of the probe tile 14, such as at opening 17. It will beappreciated that the tips can be appropriately arranged in variousconfigurations and various needle/tip arrays so as to accommodate adevice to be tested. The channel 15 provides an inlet and outlet foreach probe wire 30, and allows the probe wires 30 to extend from thewire guide 16 into the probe tile 14, and then out of the probe tile 14to an exposed or open center area of the probe card 10. For ease ofillustration, one probe wire 30 is shown as going through one channel 15of the probe tile 14 (see e.g. FIGS. 6 and 6A). However, severalchannels 15 may be present in the probe tile 14, such as for each grooveof the wire guide 16 and clamp 18, so that multiple probe wires 30 gothrough the probe tile 14.

Each probe wire 30 also includes a signal transmitting portion 30 a andan optional guard portion 30 b exposed from the wire guide 16. Thesignal transmitting portions 30 a and the guard portions 30 b form acontact pattern on one side of the probe card 10 within the groovepattern 12 of the wire guide 16. The contact pattern of the signaltransmitting portions 30 a and the guard portions 30 b, matches thecontact pattern of the circuit board 40 (further described below).

With further reference to the wire guide 16, the groove pattern 12includes holes 34. The wire guide also includes a clearance 36 at eachgroove, which allows for the probe wire 30 for example to bend enough tocontact the circuit board 40. The holes 34 allow for forming the contactof the probe wire 30 with the circuit board, such as after installation,and allow for viewing the probe wire 30 so that confirmation can be madethat a respective wire 30 is in a correct position and that propercontact has been formed. In one embodiment, the hole 34 can allow accessto the probe wire 30, for example so that it can be manipulated throughthe hole. In some examples, each groove of the wire guide 16 can havethe clearance 36.

Further description and illustration of a wire guide, probe tile, andprobe wires is in pending U.S. application Ser. No. 13/010,234, filedJan. 20, 2011, the entirety of which is incorporated by referenceherein. In one embodiment, the probe tile 14 is constructed of adifferent material than the wire guide 16, clamp 18, and retainer member20 (further described below). For example, the probe tile 14 is adielectric material and may be composed of a ceramic material forexample. In some embodiments, the retainer is a stainless steel or othersuitably stiff material. It will be appreciated that a high temperatureplastic may be employed for example for the wire guide and clamp. Itwill further be appreciated that other plastics or other suitably stiffmaterials may be employed for example if testing is conducted aroundroom temperature or not high temperatures that would require a moreresistant material.

The probe card 10 also includes a connector structure on the other sidefrom where the groove pattern 12 of the wire guide 16 is located, andthus the other side from where the contact pattern of the probe wires 30is formed. As shown, the connector structure is a retainer member 20. Inone embodiment, the retainer member 20 has a view port 26 and aretention slot 28. The view port 26 allows one, such as for example atest operator or assembler, to view the probe wires 30 through the probecard 10. This opening also allows adjusting alignment of the probes. Theretention slot 28 allows for an element to be placed within the slot 28and hold the probe card 10. The retention slot 28 allows the probe card10 to be part of a test system able to manipulate the position of theprobe card 10 and also replace it when needed. As best shown in FIGS. 5and 6, for example, the retention slot 28 is between two relativelylarger portions of the retainer member 20 (see portions above and belowthe slot 28), such that the retention slot 28 is an indentation relativeto the larger portions. In one embodiment, the slot 28 extends aroundthe retainer 20. In some embodiments, an outer portion of the retainer20 is relatively more oblong than an inner portion next to the wireguide 16 (see e.g. FIG. 5). The difference in shape, for example, can behelpful in interchanging the probe apparatus for another and can alsoprovide a keying feature such that an incorrect probe card without thedifference in shape would be prevented from being used as a replacementand/or from being interchanged.

In one embodiment, the probe card 10 has a chassis 24. As shown forexample in FIGS. 4-6A, the chassis 24 connects the probe tile 14 to thewire guide 12, clamp 18, and retainer member 20. As shown, the chassis24 has screw supports extending from the main body, where the screwsupports may extend through holes of the clamp 18 and wire guide 16 andtoward the retainer member 20. Screws 22 may be inserted into holes ofthe retainer member 20 and can be fastened to the chassis 24 in thescrew supports. It will be appreciated that the chassis, its particularstructure, including the screw supports and screws, are merely exemplaryas other structures could also be used to assemble and connect the wireguide, clamp, probe tile, and probe wires together.

Referring to the circuit board 40, FIG. 3 shows a top plan view of thecircuit board 40 alone. In one embodiment, the circuit board 40 isconfigured as a plate having a top side, a bottom side (not shown), andan opening 44 through the top and bottom sides. In one embodiment, thecircuit board 40 is a motherboard of contacts or traces that helpsdeliver signals from the probe card 10 to additional test/measurementequipment used, for example in an overall electrical diagnostic system,such as for testing semiconductor devices or other MEMS devices. Suchdiagnostic and measurement systems are known and can be adapted for usewith the probe card and circuit board described herein.

In the example shown, the plate is a circular shape, and the opening 44is generally through the center of the circular plate. It will beappreciated that other shape configurations may be employed, as well asother placement for the opening. The opening 44 of the circuit board 40allows for a probe card, e.g. probe card 10, to be placed onto thecircuit board 40 and for interchanging probe cards into the opening ofthe circuit board 40.

FIG. 3 shows a top view of the circuit board 40 alone, but further showsone embodiment of a layout for signal contacts 42 and guard contacts 46.In the example shown, the layout is a pattern of many signal contacts 42and a pattern of many guard contacts 46 in the form of contact traces onthe circuit board 40. As shown in FIG. 3, one embodiment for theconfiguration of the signal contacts 42 and guard contacts 46 is aspoke-like arrangement and configuration from the center of the plate,for example extending from the opening 44 toward the outer edge of theplate. The inner ends of the signal contacts 42 and guard contacts 46allow contact with the signal transmitting portion 30 a and guardportion 30 b respectively of the probe wires 30, so as to allowtransmission of signals from the probe card 10 to additional test andmeasurement equipment. That is, the contact pattern of the probe wires30 in the probe card 10 match the pattern of signal and guard contacts42, 46 on the circuit board 40. The structure of the wire guide 16 andclamp 18 help to secure contact and alignment of the probe card 10 withthe circuit board 40.

For example, signals transmitted through probe wires 30 of the probecard 10 from testing a semiconductor device, may be transmitted throughthe pattern of signal contacts 42 as well as the guard contacts 46. Forexample, a signal through the guard contact can be made to match thevoltage of the center conductor (e.g. signal contact) as much aspossible to minimize leakage. It is also known to apply the voltage, forexample, through a tester which continues to the probe needle, so thatthe guard signal traverses the interface between the probe card 10 andthe circuit board 40. In some embodiments for example, when probe wiresare guarded, such as for example covered with a conductive polymerdriven guard, such a guarded probe may continue from its contact at thecircuit board through the end of the probe needle. It will beappreciated that the signal trace can function without the guard onnonsensitive signals.

FIGS. 3A-3C show additional views of the circuit board 40 of FIG. 3,where in FIG. 3C less detail of the contact pattern is shown. Furtherdescription and illustration of circuit boards are also in pending U.S.application Ser. No. 13/010,234, filed Jan. 20, 2011, the entirety ofwhich is incorporated by reference herein.

In operation, each probe wire 30 includes an end configured to probe adevice (e.g. the tips 33), such as a semiconductor wafer. With referenceto the signal transmitting portion 30 a and the guard portion 30 b, thesignal transmitting portion 30 a of each probe wire 30 is configured tocontact a respective signal contact 42 in the pattern of signal contactson the circuit board 40 close to the center of the circuit board 40 andopening 44. Likewise, the guard portion 30 b of each wire 30 isconfigured to contact a respective guard contact 46 in the pattern ofguard contacts close to the center of the circuit board 40 and opening44. See arrows of FIGS. 1 and 2 leading toward the opening 44 of thecircuit board 40. As mentioned above, in some embodiment, any one ormore of the probe wires 30 may have a conductive polymer on the guardportion 30 b. It will be appreciated that the probe wires may be scaledto accommodate additional layers, such as for example, triax and quadraxtype connectors.

With further reference to the probing wires 30, characteristics andconstruction of the probing wires may vary. Previous patents, whichdiscuss probe characteristics and constructions, includes U.S. Pat. Nos.6,975,128, 6,963,207, 6,992,495, 6,586,954, and 6,201,402, all of whichare hereby incorporated by reference in their entirety, wherein one ofskill in the art could use the subject matter described in these patentsand apply it to probing wires, needles, tips, etc. of any probe testcore described herein.

The disclosure herein can provide many structural advantages, amongothers, such as any one or more as follows.

1. Radiused bottom of probe slots aids in centering probe needles toeliminate mismatch between the replaceable probe core and motherboard.

2. Holes in the frame allow final forming of contact needle as well asinspection of contact position after mating the probe card with themotherboard.

3. The distal end of the probe can be formed into a contact mechanismwhich eliminates extra parts. For example, where the probe wire 30contacts the motherboard, there is no need for separate structures tomake the contact, such as for example spring pins are not needed to makethe contact. Thus, in some configurations for example, the probe wiresare constructed to become the contact by special bending. For example,special bending entails forming the probe wire with a geometry, suchthat contact is made with the motherboard with the proper force andsurface area to ensure low contact resistance between the probe wiresand motherboard. For example, the contact force may be determined by theunsupported length of the probe wire. For example, the contact surfacearea may be determined by the radius on the contact. In some instances,it is desired to balance the contact force and contact surface area, sothat the contact will not have high resistance, which can preserve themotherboard from wearing out prematurely.

Functionally, the test systems, apparatuses, and equipment hereinincluding for example the probe card and motherboard have observedvarious one or more of the following benefits, among others, which areoutlined below.

1. The probe card is of relatively small size which can save space andcosts, while providing ease of manufacture and rebuild.

2. The probe card can provide good contact and crash resistance anddurability (e.g. using cantilever design of earlier patents incorporatedby reference above).

3. The probes (i.e. probe wires) of the probe card can be constructedand configured so as to provide low noise and low leakage and lowcapacitance, and also operate within wide temperature ranges. Lowleakage performance (e.g. fA/V) has been observed, for example, when100V is applied to one needle/pin and all other pins are grounded attemperatures of 25° C. and 200° C. Results have shown that low leakageperformance of the probes have been obtained, for example, at about 5fA/V and about 1 fA/V at temperatures of about 25° C., and also at about0.5 pA/V and about 2 fA/V at temperatures of about 200° C. Differencescan depend upon the probe configuration, for example, the structure andconfiguration of the coating or guard on the probes.

4. The probes of the probe card can allow for high current and voltagetesting, while maintaining fault tolerance.

5. The probes can have uniform beam length.

6. The motherboard is configured to perform over a wide range oftemperatures, for example, between −65° C. to 220° C.

With further reference to the probe card 10, identification capabilitiesmay be employed to ensure that the proper probe card and circuit boardare being applied for testing.

One embodiment of this is the use of unique identification resistorsattached to the probe card 10. As best shown in FIGS. 5 and 7, resistors52 are disposed on the wire guide 16. In one embodiment, the wire guide16 includes a cavity 38, where the resistors 52 are located. Channels 35allow wires 56 to electrically connect the resistors 52 to the circuitboard, e.g. circuit board 40, by way of contact of the wire 56 with thecircuit board 40. For example, one wire 56 connected to a resistor 52 isshown extending through a channel 35 and forming a contact 58. Thecontact 58 makes contact with one of the signal contact traces of thecircuit board 40. That is, if identification resistors (e.g. resistors52) are employed such contacts 58 can otherwise take the place of aprobe wire 30 contact and respective probe trace of the circuit board 40at that particular location of the wire guide 16.

Standard test equipment may be used to read the resistor through thecontact 58 of the wire 56 with the circuit board 40.

In other embodiments, the circuit board 40 can include its ownidentification resistors. As shown in FIG. 3, location 50 indicateswhere on the board 40 resistors can be placed. In other examples, aresistor pattern R may be at about the 3:00 position in FIG. 3 c.Identification resistors on the circuit board 40 can allow for adetermination to be made as to whether the correct circuit board isbeing used. As with the resistors on the probe card, it will beappreciated that standard test equipment may be used to read theresistors on the circuit board 40, such as at location 50. In someembodiments, the circuit board 40 can include traces for temperaturefeedback. For example, on either side of leader line 44 (e.g. shorttraces) can be where such traces are located. In other examples, tracesT may be at about the 9:00 position in FIG. 3 c. Such traces can be usedfor incorporating a temperature resistor/feedback capability.

As described above, a probe apparatus generally is structured as a probecard that on one side has a contact pattern. The contact pattern is forcontacting a respective contact pattern on another test equipment orcomponent, such as a circuit board. The contact pattern of the probecard includes probe wires with tips that probe a device desired fortesting. Signals are transmitted through the probe wires from the probecard, for example, through a circuit board to other diagnosticequipment. The contact of the probe card with the circuit board allowssignals to be transferred through the probe wires to the otherdiagnostic equipment.

On another side of the probe card is a connector structure. Theconnector structure allows the probe card to be connected ordisconnected from a holder.

FIGS. 8-10 show one embodiment of a holder 70. Generally, the holder 70allows for a probe card (e.g. probe card 10) to be replaced with anotherprobe card. Such other probe card may be for example another probe cardwith a different contact pattern or another probe card that may be areplacement for a used probe card. In some embodiments, the holder 70has multiple probe cards connected to it, and is configured to allow forinterchanging among the probe cards connected to the holder 70, such asfor changing a probe card between testing. In some embodiments, theholder can be part of a system used to test devices, where the holder 70is able to manipulate and position the probe card as needed.

In the embodiment shown, the holder 70 has a structure that allows forsupporting multiple probe cards. The holder 70 allows for interchangingprobe cards, such as with respect to a testing need, for example if adevice to be tested requires a different probe tip pattern or needlearray for testing. It will be appreciated that probe cards may differ intheir probe tip pattern, for example to accommodate the device beingtested. The holder 70 may also allow for interchanging probes such asfor the need to replace an old probe card with a new probe card that isthe same as the one already used, but perhaps no longer functioning asrequired. It will be appreciated that the descriptions with respect tothe holder are merely exemplary, as the probe cards may also be replacedwith other diagnostic tools. For example, one or more of, or all theprobe needle contacts may be shorted together to test contact resistanceat the circuit board.

As shown in FIGS. 8-10, the holder 70 includes a main body 72 withseveral surfaces 74. Each surface 74 represents a location where a probecard, e.g. probe card 10, can be held. In the embodiment shown, theholder 70 has five surfaces 74 and the main body 72 is in the shape of apentagon wheel. A connector hole or axle hole 78 allows the holder 70 toconnect to another equipment that can rotate or revolve the holder 70about the axis A through the hole 78, so as to switch from one probecard to another. Such other equipment can have a spindle (not shown)that is inserted into the hole 78 and thereby rotate the holder 70. Itwill be appreciated that switching from one probe to another can beconfigured as an automated process, where appropriate controlling,processing, and mechanical hardware are employed as necessary tomanipulate the holder. It will also be appreciated that pneumaticoperation of the holder can be employed so as to eliminate or at leastreduce electrical interference with the operation of the probe card.

It will be appreciated that the pentagon wheel structure of the holderis not meant to be limiting, the holder could be constructed as a wheelof other polygonal shapes as appropriate, such as for example a square,triangle, hexagon, or the like. It also will be appreciated that aholder does not have to rotate or revolve to switch from one probe cardto another. Other implementations for switching the probe card can beemployed. For example, a holder may be configured to translate betweenprobe cards to move the probe cards into/out of probing positions (seee.g. FIG. 15 and described further below).

With reference to the details of the holder 70, an opening 76 isincluded through each of the surfaces 74. The opening 76 allows for partof the retainer member, e.g. retainer member 20 of probe card 10, to beinserted through the opening 76.

A sliding clip 80 connects the probe card 10 to the holder 70. Thesliding clip 80 is slidable along the surface 74 of the holder and canbe retained on the main body 72. The sliding clip 80 has a curved edge82, for example in the shape of a U that engages the slot 28 on theprobe card 10. See B in FIG. 9 pointing to the slot of the probe coreand the curved edge 82 of the sliding clip 82. In one embodiment, theradius of the curved edge 82 is smaller than the radius and curvature ofthe opening 76, such that the sliding clip 80 will engage the slot 28 ofthe probe card 10, but will not allow the probe card 10 to fall out ofthe opening 76. That is, a portion of the retainer member 20 is able tobe inserted into the opening 76, where the sliding clip 80 can be movedto engage the slot 28, but not allow the inserted portion of theretainer member 20 to fall out of the holder 70. Thus, the relativelarger portions of the retainer member 20 are on opposite sides of thesliding clip 80, which allows the holder 70 to hold the probe card. FIG.8 shows a perspective view of the holder with one clip in thenon-holding position, with the clip open and ready to receive a probecard, as well as another clip in the holding position. FIG. 9 shows theholder 70 just prior to connection with a probe card. FIG. 10 shows theprobe card connected and held by the holder 70. FIG. 10 also shows aplate that can contain the sliding clip 80. For example, the plate canextend from the holder 70 and can be disposed between the probe card 10and the holder 70. See also the top of the holder 70 in FIG. 9. Theplate for example can provide another platform that is on top of theclip 80 before the probe card is placed onto the holder 70.

FIGS. 11-14 show another embodiment of a probe apparatus 100. The probeapparatus 100 is similar to the probe apparatus 10, but has a connectorstructure that is different from the retaining member and slotconfiguration of the probe apparatus 10, among other differences.Similar to probe apparatus 10, the probe apparatus 100 includes a wireguide 106 with a groove pattern 102, a clamp 108, and a probe tile 104.The probe tile 104 can have a tab and notch structure 104 a for examplefor mating with a circuit board, e.g. 40. The probe tile 104 can beassembled with the wire guide 106 and clamp 108 for example through achassis 124. As with probe apparatus 10, the probe apparatus 100 alsoincludes probe wires 130 with probe needles 132 and probe tips 133 forcontacting the semiconductor device, such as for example a semiconductorwafer or MEMS device. The probe tile 104 can also include one or morechannels (not shown), but e.g. such as channels 15 of apparatus 10. Anopening 107 in the probe tile 104 allows the probe tips 133 to extendout of and be exposed from the probe tile 104. Each of the probe wires130 include a signal transmitting portion 130 a and a guard portion 130b. Other structures, configurations, and materials similar to probeapparatus 10 are not further described. It will be appreciated that theprobe apparatus 100 can also incorporate the identification capability,e.g. use identification resistors, in the same or similar manner asdescribed above with respect to probe apparatus 10.

With particular reference to FIGS. 12-14, the probe apparatus 100 showsa different connector structure than for example the probe apparatus 10.The connector structure of probe apparatus 100 is configured as a balland socket type mount, where a retainer member 120 includes a socketarea 125. In one embodiment, the retainer member 120 for example isconstructed of a main body that can be connected for example to the wireguide 106 by screws 122. In one embodiment, the socket 125 is configuredto receive a ball mount member 128.

In one embodiment, the ball and socket mount can allow slight movement,such as tilting movements, of the probe card which can facilitate goodmating, for example to a circuit board. As shown, the retainer member120 is configured to include the socket 125 or opening on one side ofthe probe apparatus 100. One or more supports 126 can be positionedtoward the outer portion of the socket 125. The socket 125 is configuredto receive the ball mount member 128, while the supports 126 allow forthe ball mount member 128 to be fitted within the socket 125. The ballmount member 128 and socket 120 thus can provide another mountconfiguration. In the example shown, four supports 126 are shown, but itwill be appreciated that more or less supports may be employed asappropriate and/or necessary. It will be appreciated that each support126 may have some area of clearance on the other side from which itengages the ball mount member 128, which can allow for some movement ofthe supports to allow for the ball mount member 128 to be fitted in thesocket 125.

With reference to the ball mount member 128, it will be appreciated thatthe ball mount member 128 may be part of and/or be removably connectedwith another holder equipment. For example, a hole 129 may allow theball mount member 128 to be connected to a holder equipment that isconfigured to allow interchanging and/or replacement of a probeapparatus, e.g. probe apparatus 100. For example, the holder asdescribed above may be modified to connect to the ball mount member 128rather than using the retainer slot and clip configuration. For example,a member on a holder may be inserted into the opening 129 of the ballmount member 128 to retain the ball mount member 128, thus retaining theprobe apparatus 100 when the ball mount member 128 is connected to thesupports 126 of the socket 125. It will be appreciated that depending onthe holder employed, the probe apparatus 100 may be replaced with theball mount member 128 or be replaced from the ball mount member 128,e.g. disconnecting the ball and socket engagement. It will beappreciated that in some embodiments, the ball and socket can beinterchanged, for example, the ball mount member can be on the probecard and the socket on a holder to which the probe card may beconnected.

FIGS. 17-20 show another embodiment of a probe apparatus 300 or probecard. The probe apparatus 300 is similar to the probe apparatus 100, andis similar to probe apparatus 10, but has a connector structure that isdifferent from the retaining member and slot configuration. Similar toprobe apparatus 100, the probe apparatus 300 includes a wire guide 306with a groove pattern 302, a clamp 308, and a probe tile 304. The probetile 304 can have a tab and notch structure 304 a, 304 b for example formating with a circuit board, e.g. 40, and for connection/disconnectionof the probe card. The probe tile 304 can be assembled with the wireguide 306 and clamp 308 for example through a chassis 324. As with probeapparatus 100, the probe apparatus 300 also includes probe wires (e.g.probe wires 130 from probe card 100) with probe needles (e.g. probeneedles 132 from probe card 100) and probe tips (e.g. probe tips 133from probe card 100) for contacting the semiconductor device, such asfor example a semiconductor wafer or MEMS device. The probe tile 304 canalso include one or more channels (not shown), but e.g. such as channels15 of apparatus 10. Probe card 300 can also have an opening (e.g.opening 107 from probe card 100) in the probe tile 304 to allow theprobe tips (e.g. 133) to extend out of and be exposed from the probetile 304. Each of the probe wires (e.g. 130) can include a signaltransmitting portion and a guard portion (e.g. signal transmittingportion 130 a and guard portion 130 b from probe card 100). Otherstructures, configurations, and materials similar to probe apparatus 100and 10 are not further described. It will be appreciated that the probeapparatus 300 can also incorporate the identification capability, e.g.use identification resistors, in the same or similar manner as describedabove with respect to probe apparatuses 100 and 10. In one embodiment,resistor 350 may be used, which is similar to 52 of probe apparatus 10,and can also be employed to monitor the function of the probe card, e.g.operating temperature. It will be appreciated that a diode may also beemployed.

With further reference to wire guide 306, in some embodiments, the wireguide 306 may employ a beveled edge 310 at portions of the perimeter ofthe wire guide 306. The beveled edge 310 can allow for ease of placementand mounting of the probe card 300 when it is to be used and contactedfor example to a circuit board (e.g. 40) and device under test such as asemiconductor device. In some embodiments, as also shown in probe card100, the wire guide 306 may also have a notch structure 312 which canfurther help with alignment and placement of probe card 300 when it isto be in use.

As with probe card 100, the probe apparatus 300 shows a differentconnector structure than for example the probe apparatus 10. Theconnector structure of probe apparatus 300 is configured as a sockettype mount, for ball and socket type connection, where a retainer member320 includes a socket 325. In one embodiment, the retainer member 320for example is constructed of a main body that can be connected forexample to the wire guide 306 by screws 322. In one embodiment, thesocket 325 is configured to receive a ball mount member 328, which canbe part of an indexing mechanism that is further described below.

In one embodiment, the socket mount can allow slight movement, such astilting movements, of the probe card which can facilitate good mating,for example to a circuit board. As shown, the retainer member 320 isconfigured to include the socket 325 or opening on one side of the probeapparatus 300. One or more supports 326 can be positioned toward theouter portion of the socket 325. The socket 325 is configured to receivea ball mount member 328, while the supports 326 allow for the ball mountmember 328 to be fitted within the socket 325, such as by a press fit orinterference fit. The ball mount member 328 and socket 325 thus canprovide another mount configuration. In the example shown, four supports326 are shown, but it will be appreciated that more or less supports maybe employed as appropriate and/or necessary. It will be appreciated thateach support 326 may have some area of clearance on the other side fromwhich it engages the ball mount member 328, which can allow for somemovement of the supports to allow for the ball mount member 328 to befitted in the socket 325.

With reference to the ball mount member 328, it will be appreciated thatthe ball mount member 328 may be part of and/or be removably connectedwith another holder equipment. For example, a hole 329 may allow theball mount member 328 to be connected to a holder equipment that isconfigured to allow interchanging and/or replacement of a probeapparatus, e.g. probe apparatus 300. For example, the holder asdescribed above may be modified to connect to the ball mount member 328rather than using the retainer slot and clip configuration. For example,a member on a holder may be inserted into the opening 329 of the ballmount member 328 to retain the ball mount member 328, thus retaining theprobe apparatus 300 when the ball mount member 328 is connected andfitted to the socket 325. It will be appreciated that, depending on theholder employed, the probe apparatus 300 may be replaced together withthe ball mount member 328 or it may be replaced from the ball mountmember 328, e.g. disconnecting the ball and socket engagement.

FIGS. 15 and 16 are perspective views of one embodiment of translationalindexing 200 of multiple probe apparatuses. As noted above, a holder maybe configured to translate between probe cards. FIG. 15 shows oneembodiment of such translational indexing. Different from a rotationalindexer, such as holder 70, FIG. 15 shows a circuit board 400 forinterchanging probe cards. For example, probe apparatus 100 may beemployed as the probe cards in such a translational indexingimplementation. Four interchangeable probe cards 100 are shown, but itwill be appreciated that more or less than four probe cards may beemployed.

In one embodiment, probe card 100 in the center of the circuit board400, may be selected, moved and then dropped into the probing position.In one embodiment, an actuator or other movable component, can select aprobe card 100, and then move and drop it into the probing position.Likewise, a probe card 100 in the probing position can be lifted andmoved out of the probing position and, for example, replaced with adifferent probe card. FIG. 16 shows an example of a canter or actuatorstructure for moving the probe cards 100. In one embodiment, such astructure may be configured for example as an arm 210 that can selectand move a probe card 100 as needed into and out of the probingposition, and to replace a probe card 100.

It will be appreciated that switching from one probe to another can beconfigured as an automated process, where appropriate controlling,processing, and mechanical hardware are employed as necessary tomanipulate the holder. It will also be appreciated that pneumaticoperation of the holder can be employed so as to eliminate or at leastreduce electrical interference with the operation of the probe card.

FIGS. 21-27 show one embodiment of a testing system 400, includingmultiple sectional views of the system 400. Generally, a holderstructure 470 is shown with a carriage and indexing components. In theembodiment shown, the holder 470 has a structure that allows forsupporting multiple probe cards, for example the holder 470 can beconstructed as a pentagon wheel where, on each side 476 of the pentagon,a probe card (e.g. probe cards 100, 300) may be mounted. The carriage isan assembly on a frame that moves the holder so as to put a probe cardmounted thereon into contact with both a device under test (e.g.semiconductor wafers) and a circuit board 440 (or e.g. 40). The carriagefor example moves the holder 470 up and down to contact a probe cardwith the circuit board 440. The carriage also can rotate the holder 470so as to move from one side of the holder 470 (e.g. pentagon as shown)to another side of the holder 470, which allows for a different probecard on the holder 470 to be used, for another probe card to be mounded,and/or for a probe card on any side of the holder to bereplaced/removed.

The system 400 can include the circuit board 440, the holder 470, andthe carriage assembly which includes a frame structure and indexingcomponents, the details of which are further described below.

In one embodiment, the frame includes a top plate 401 connected to alower plate 411, such as by a wire channel 419 that may be used a wireguide for wires extending along wire groove 420. A carriage mid-frame412 is between the top plate 401 and lower plate 411 and is connected tothe holder 470 using a shaft 480 extending through an opening 478 of theholder 470, which also allows for rotation of the holder on the carriage(see e.g. FIG. 23). The carriage mid-frame 412 is connected with the topplate 401 and is allowed to move up and down relative to the top plate401 by use of pneumatic control. With specific reference to FIG. 24 forexample, an air lift cylinder 408 is shown connected to the carriagemid-frame 412 and is used to move the frame 412 up and down relative toa device under test and the circuit board 440. The air lift cylinder 408can be connected to an air source. The carriage can be spring loaded andcan include for example a hold down spring 405 around a lift guidebushing 414 and a lift guide shaft 416 to guide the frame 412. The holddown spring 405 can provide a downward force on the probe card, whilethe air cylinder 408 can help fix the carriage in place. The pneumaticlift can eliminate or at least avoid electrical noise near wheremeasurements are taken. In some embodiments, a lift stop 415 may beemployed to limit movement of the frame 412 in the up and downdirections.

With further reference to the holder 470, each side 476 of the holder470 can include the ball mount 328 described above, such that a socketon a probe card (e.g. probe cards 100, 300) can be mounted onto theholder 470. As shown in FIGS. 22 and 23, for example, one probe card 300is mounted and in probing position. As one example, the ball mount 329can be connected to the holder 470 by a screw and the socket (e.g. 325)of the robe cards can be snap fitted with the ball mount 328.

With reference to the indexing components, the system 400 may employ forexample an index slide and index drive construction to move the holder470, where index slide 406 moves from one position to another positionto engage the holder 470 and rotate it around the shaft 480. See e.g.FIGS. 25 and 26. The index slide 406 can be driven by index driver 404,which can be pneumatically activated such as by an index air cylinder417 and connected to an air source. In one embodiment, the holder 470has index drive pins 418 thereon that can be engaged by a hook or pawl422 connected to the index slide 406. For example, the holder 470 can berotated to switch out a probe card (e.g. probe card 300) from theprobing position and also to allow replacement/removal of probe cardfrom any of the sides of the holder 470. The carriage moves the holder470 upward to allow the index driver 404 to engage the index slide 406,such as by a protrusion and recess engagement of the index driver 404and the index slide 406. The index driver 404 can then be moved toimpart movement on the index slide. For example, as shown in FIG. 26,the index slide 406 can move to the left so that the pawl 422 can engageone of the index drive pins 418 on the holder 470 and rotate the holder470. In some embodiments, the index slide 406 can be connected to anindex return spring 413 to allow the index slide 406 to move back to thenon-index position, for example back to the right when the index driver404 disengages from the index slide 406. With reference to the pawl 422,the pawl 422 can be movable around a pivot 425, and connected to areturn spring 423, which allows the pawl 422 to pivot or otherwise moveto a non-index position so as not to engage one of the index drive pins418.

The system 400 can also include a dock portion, such as for exampledocking block 402 and ports with seals, e.g. o-ring seals. The dockingblock 402 provides a pneumatic/pressure and electrical interface of thesystem 402, for example with the testing/measurement equipment. In theembodiment shown, the docking block 402 is on top of the top plate 401,and can have a clearance or recessed area to allow clearance for dockingequipment, such as rods or other clamp structures. The docking block 402can be pinched on sides so that the pressure and electrical connectionscan be made. The o-rings 403 allow seal for air to enter into thesystem, for example the air lift cylinder 408 and the air cylinder 417of the index drive 404. The docking equipment delivers pressured air tothe air cylinders and can also have electrical contacts to electricallycontact the docking block 402, such as when a clamp engages or pinchesthe docking block 402. The electrical connection can be used for exampleto read the ID resistors

In some embodiments, further alignment structures may be employed tohelp the probe card be placed into probing position. For example, anadditional plate 421 as shown for example in FIGS. 23 and 27 may bedisposed between the circuit board 440 and the lower plate 411. Theplate 421 can be somewhat flexible to allow fit with the probe card whenit is positioned onto the circuit board 440 and device to be tested. Insome embodiments, the plate 421 can include a detent bump 427 that maybe somewhat flexible and allow for example the notch structure 312 ofprobe card 300 to align and engage in the correct position. FIG. 27shows a top plan view of the system 400 with much of the carriage andframe structures removed so that the plate 421 can be seen.

It will be appreciated that the system 400 on the circuit board 440 canalso incorporate identification capability and resistance measurement,e.g. use identification resistors, in the same or similar manner asdescribed above with respect to circuit board 40 and probe apparatuses100 and 10. In one embodiment, resistor 452 may be used. Identificationresistors on the circuit board 440 can allow for a determination to bemade for example as to whether the correct circuit board is being used.As with the resistors on the probe card, it will be appreciated thatstandard test equipment may be used to read the resistors on the circuitboard 440. In some embodiments, the circuit board 440 can include tracesfor temperature feedback similar to circuit 40 above. Such traces can beused for incorporating a temperature resistor/feedback capability.

FIG. 28 is one embodiment of a loading tool 500. The loading tool 500can be useful to load and remove a probe card, e.g. 100, 300, from aholder, e.g. holder 470 and can avoid contact with the probe tips on theprobe card and avoid the risk of particulate getting into the probearray. The loading tool 500 includes an actuator 502, such as a button,and includes a probe card engaging end. The probe card engaging end hasan internal rod 504, notches 506, and an engaging member 508, such as aball. The loading tool has a main body that can be a handle 510. In oneembodiment, when the button or actuator 502 is up, the rod 504 is upwhich can rotate the ball into the slot (e.g. slot 304 b of the probecard 300), thus retaining the probe card so it can be loaded onto aholder or removed from a holder (e.g. holder 470). When the button oractuator 502 is pushed down, the rod 504 is pushed down which rotatesthe ball out of the slot to liberate the probe card (e.g. slot 304 b ofprobe card 300). Thus, by activating the actuator 502, e.g. pushing thebutton down or pushing the button to release it up, the loading tool 500can disengage/engage the probe card. In some embodiments, the probe cardengaging end can rotate when the button is pushed to move the engagingmember 508.

FIG. 29 is a perspective view of one embodiment of packaging 600 for atesting system. In some embodiments, the packaging 600 is plastic andhas a lid 602 and base 604 in the form of a Tupperware-like container.The packaging 600 can be configured to contain for example the testingsystem 400 as a single unit, including for example the circuit board(e.g. 40) and carriage, holder, and carriage frame), and be shipped asmultiple units.

FIGS. 15 and 16 are perspective views of one embodiment of translationalindexing 200 of multiple probe apparatuses. As noted above, a holder maybe configured to translate between probe cards. FIG. 15 shows oneembodiment of such translational indexing. Different from a rotationalindexer, such as holder 70, FIG. 15 shows a circuit board 400 forinterchanging probe cards. For example, probe apparatus 100 may beemployed as the probe cards in such a translational indexingimplementation. Four interchangeable probe cards 100 are shown, but itwill be appreciated that more or less than four probe cards may beemployed.

In one embodiment, probe card 100 in the center of the circuit board400, may be selected, moved and then dropped into the probing position.In one embodiment, an actuator or other movable component, can select aprobe card 100, and then move and drop it into the probing position.Likewise, a probe card 100 in the probing position can be lifted andmoved out of the probing position and, for example, replaced with adifferent probe card. FIG. 16 shows an example of a canter or actuatorstructure for moving the probe cards 100. In one embodiment, such astructure may be configured for example as an arm 210 that can selectand move a probe card 100 as needed into and out of the probingposition, and to replace a probe card 100.

It will be appreciated that switching from one probe to another can beconfigured as an automated process, where appropriate controlling,processing, and mechanical hardware are employed as necessary tomanipulate the holder. It will also be appreciated that pneumaticoperation of the holder can be employed so as to eliminate or at leastreduce electrical interference with the operation of the probe card.

FIGS. 30 to 34 show another embodiment of translational indexing ofmultiple probe apparatuses. As noted above, a holder may be configuredto translate between probe cards. FIGS. 30 to 32 show one embodiment ofsuch translational indexing. Different from a rotational indexer, FIGS.30 to 32 show a translational indexer 800 where the carriage structureis constructed as having multi-position plate 802 for interchangingprobe cards within a center static plate 804. The multi-position plate800 has locations with slots 806 for a probe card 700 to be arrangedtherein. The center plate 804 has a probe position 808 at which one ofthe probes 700 can be positioned. The center plate 804 has an entry thatcan communicate with the slots 806 (see arrow) to allow, for example, aprobe card 700 to slide toward and down into the probe position 808 ofthe center plate 804. In some embodiments, the multi-position plate 802can be rotatable relative to the center plate 804, or vice versa, toallow alignment of any one of the slots at one time with the entry intothe probe position 808 of the center plate 804. It will be appreciatedthat either of the center plate 804 and multi-position plate 802 may bestatic relative to the other, or may both be rotatable to communicatethe slot 806 and entry into the probe position 808. It will beappreciated suitable mechanical structures may be employed to engage theprobe cards 700 as needed to slide them along the slot 806 into and outof the probe position 808.

FIGS. 33 and 34 show an individual probe card 700 which is anotherembodiment of a probe card. As with the probe cards described earlier,probe card 700 has a wire guide 702 and a probe tile 704 held togetherby a chassis 724. The probe card 700 can also have a retainer structure706, such as on the chassis 724 to allow for other test components, suchas a suitable holder to engage the probe card 700 and position it asneeded. In some embodiments, the retainer 706 can be a twist lockfeature on annular surface of the chassis 724, which can be engaged by asuitably structured holder. It will be appreciated this configuration ismerely exemplary.

It will be appreciated that switching from one probe to another can beconfigured as an automated process, where appropriate controlling,processing, and mechanical hardware are employed as necessary tomanipulate the holder. It will also be appreciated that pneumaticoperation of the holder can be employed so as to eliminate or at leastreduce electrical interference with the operation of the probe card.

The numerous innovative teachings of the present application have beenset forth above with particular reference to presently preferred butexemplary embodiments, wherein these innovative teachings areadvantageously applied, for example to the particular problems of aprobe needle for measuring low currents with a wide operatingtemperature range in probing a semiconductor device. However, it shouldbe understood that these embodiments are only examples of the manyadvantageous uses of the innovative teachings herein. In general,statements made in the specification of the present application do notnecessarily limit any of the various claimed inventions. Moreover, somestatements may apply to some inventive features but not to others. Ingeneral, unless otherwise indicated, singular elements may be in theplural and vice versa with no loss of generality.

The following terms have been particularly described throughout thedescription and are not intended to be limitative:

Semiconductor Device not Limitive

The present disclosure is particularly suitable for probingsemiconductor devices, but the use of the present teachings is notlimited to probing semiconductor devices. Other devices may be appliedto the present invention teachings. Thus, while this specificationspeaks in terms of probing ‘semiconductor’ devices, this term should beinterpreted broadly to include probing any suitable device.

Low Current not Limitive

The present disclosure can solve the problem of measuring currents below100 fA, but the current range of the present teachings is not limited tobelow 100 fA. For example, the present invention may be applied tomeasure the currents at or above 100 fA in a semiconductor device. Thus,while this specification speaks in terms of ‘low currents’ or ‘measuringcurrents below 100 fA’, these terms should be interpreted broadly toinclude any current that flows through a semiconductor device whichcould be at or above 100 fA. In a grounded guard controlled impedanceconfiguration the present invention also solves the problem of measuringhigh frequency signals at high temperatures.

Wide Temperature not Limitive

The present disclosure can solve the problem of measuring currents of asemiconductor device in a narrow or limited operating temperature range.The present teachings do not limit to a specific operating temperaturerange. The present application allows a tester to electrically probesemiconductor devices over a wide operating temperature range, not onlyat a low operating temperature but also a high operating temperature,e.g. an operating temperature up to 300° C. and beyond. Thus, while thisspecification speaks in terms of ‘wide temperature range’ or ‘measuringcurrents in a wide operating temperature range’, these terms should beinterpreted broadly to include any suitable operating or testingtemperature range of a semiconductor device.

Probe not Limitive

The present disclosure can solve the problem of measuring currents of asemiconductor device using a shielded probe, for example a co-axialshielded probe. However, nothing in the teachings of the presentinvention limits application of the teachings of the present inventionto a probe needle with more or less layers if appropriate and/ordesired. Advantageous use of the teachings herein may be had with aprobe needle of any number of layers. Use of optical or RF signaldevices can replace probe needles for signal acquisition.

Signal Contact/Cable and Guard Contact/Cable not Limitive

The present disclosure can solve the problem of measuring currents of asemiconductor device using a co-axial or a tri-axial signal cable.However, nothing in the teachings of herein limits application of theteachings of the present disclosure to a signal cable with more or lesslayers. Advantageous use of the teachings herein may be had with asignal cable of any number of layers.

Metals not Limitive

Throughout the discussion herein have been references to metals inregards to needle and driven guard. The present disclosure does notrecognize any limitations in regards to what types of metals may be usedin affecting the teachings herein. One skilled in the art will recognizethat any conductive material may be used with no loss of generality inimplementing the teachings of the present disclosure.

Dielectric not Limitive

Throughout the descriptions herein reference has been made to the termdielectric. The present disclosure does not recognize any limitations inregards to what types of dielectric may be used in affecting theteachings herein. One skilled in the art will recognize that anynon-conductive, highly heat-resistant material may be used with no lossof generality in implementing the teachings of the present disclosure.

The embodiments disclosed in this application are to be considered inall respects as illustrative and not limitative. The scope of theinvention is indicated by the appended claims rather than by theforegoing description; and all changes which come within the meaning andrange of equivalency of the claims are intended to be embraced therein.

The invention claimed is:
 1. A system for testing a device under test,comprising: a circuit board having a pattern of signal contacts and apattern of guard contacts, the circuit board is configured as a platehaving a top side, a bottom side, and an opening through the top andbottom sides; a probe card including a wire guide, a probe tileconnected with the wire guide, a plurality of probe wires supported bythe wire guide and probe tile, the probe wires are positioned throughthe wire guide and the probe tile, the probe wires include a probe tipextending through the probe tile, the probe tips forming an array toprobe the device under test, the probe wires including a signaltransmitting portion and a guard portion exposed from the wire guide,the signal transmitting portions and the guard portions form a contactpattern and, with the array, are disposed on one side of the probe card,and a retainer member is disposed on another side of the probe card; aholder having multiple probe card stations, the probe card stations havea connector structure to connect to and disconnect from the retainermember of the probe card, and to allow the probe card to both contactthe circuit board and the device under test; and a carriage mechanismconfigured to position the probe card onto the circuit board, thecarriage mechanism to position any of the probe card stations to allowconnection to and disconnection from other probe cards, to interchangeamong the probe card and the other probe cards, and to position one ormore of the other probe cards to contact the circuit board, wherein theprobe tile is insertable into the opening of the circuit board to allowthe array to probe the device under test, and the contact pattern of theprobe card is contactable with the pattern of signal contacts and guardcontacts on the circuit board, such contact of the probe card with thecircuit board allows signals to be transferred through the probe wiresand circuit board.
 2. The system of claim 1, wherein the retainer memberincludes a socket where the socket is configured to receive a ballmount.
 3. The system of claim 1, wherein the holder includes at leastfive locations on which the probe card is mountable, and on which otherprobe cards are mountable.
 4. The system of claim 3, wherein the holderis a pentagonal wheel having five faces, each of which is mountable fora probe card, the pentagonal wheel is configured to perform rotationalindexing of the probe cards.
 5. The system of claim 1, wherein theholder is configured to switch from one probe card to another through apneumatic operation and an automatic control.
 6. The system of claim 1,wherein the holder is configured to perform translational indexing ofthe probe cards.
 7. The system of claim 1, wherein the carriagemechanism includes a frame and indexing components.
 8. The system ofclaim 1, further comprising a loading tool to load and remove probecards from the holder.
 9. The system of claim 1, further comprising apackaging to contain the circuit board, holder, and carriage mechanismas a single unit.
 10. A method of probing devices under test,comprising: positioning a holder into a probe position, which includesretaining a probe card on a side of the holder; positioning, using acarriage mechanism connected to the holder, the probe card onto acircuit board and onto a device under test, the circuit board having apattern of signal contacts and a pattern of guard contacts, the probecard including a plurality of probe wires, the probe wires including aprobe tip extending through a probe tile, the probe tips forming anarray to probe the device under test, the probe wires including a signaltransmitting portion and a guard portion exposed from a wire guide, thesignal transmitting portions and the guard portions form a contactpattern and, with the array, are disposed on a side of the probe cardthat is different from the side retained to the holder; indexing, usingthe carriage mechanism, the probe card to make aligned contact of thecontact pattern of the probe card with the pattern of signal contactsand the pattern of guard contacts, and to make contact of the array withthe device under test; probing the device under test using the array;and transmitting signals through the array to a test equipment by way ofcontact of the probe card with the circuit board and of contact of theprobe card with the device under test, which allows signals to betransferred through the probe wires and circuit board.
 11. The method ofclaim 10, further comprising replacing the probe card with another probecard.
 12. The method of claim 10, further comprising rotating the holderto switch to one of at least four other probe cards.
 13. The method ofclaim 10, wherein the one or more of the steps of positioning theholder, positioning the probe card, and indexing the probe card beingthrough a pneumatic operation and an automated control.